Comment by devaboone | Hacker News Reader

Comment by devaboone | Hacker News Reader

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Calcium metabolism is complicated, but there are a few things that are straightforward. 1. Vitamin D helps the intestines absorb calcium, so taking more Vitamin D can lead to more calcium being absorbed in your intestines, and thus more calcium in the blood. The excess calcium in your blood is caused by increased absorption from the intestines, not from bone release. (High calcium with parathyroid disease is caused by bone release, as well as increased intestinal absorption) 2. Taking calcium supplements along with Vitamin D will allow your intestines to absorb more of the calcium you are taking. 3. There are several reasons for having a lot of calcium in the urine. Primary hyperparathyroidism can do it, and in this case you will see high blood calcium levels also. If the blood calcium is low or normal (under 10.0 mg/dl), then you have another reason for high urine calcium.

Do you know what could be happening if taking vitamin D gives you severe headaches that last for days and gradually get weaker?

If you need more information, please ask away.

As someone who has worked on various deficiencies over the years, including vitamin D, I will suggest it means the dose you are taking is probably too high. When I had similar issues, reducing my sun exposure -- which was how I was improving my vitamin D status at the time -- resolved the headaches and vomiting that I was experiencing.

Thanks for the response. I'm surprised you can even get too much D with sun exposure. The thing is: I used to take vitamin D supplements fairly regularly, but now I barely take any. I will go weeks without supplementing, but when I do, I get headaches. No increased urination though, which would happen if i had excess calcium, and no nausea/vomiting.

Last time, i tried 5000IU, but this came after weeks of not taking any D supplement, and I've not taken any since. My reasoning is: that would effectively make the average dose < 400 IU, so shouldn't give me any problems, yet it does. Maybe I'm getting more from the sun than i realize :/

I'm surprised you can even get too much D with sun exposure.

I'm a special case. Trying to explain that is probably a can of worms.

shouldn't give me any problems, yet it does

There may be other factors there, which I could potentially speculate on. But A. It tends to be a can of worms when I start speculating like that and B. You didn't initially give enough info to really warrant such speculation. You only gave enough to make me feel like the safe bet was to comment on the dosage and leave it at that.

I understand. Thank you :)

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